• Suits GM LS Gen 3 & 4 engines with LS1/LS2/LS6 cathedral port heads
• 2500-7000rpm range, ideal for high performance engines
• Cast aluminium, natural finish
• Suits square bore 4 barrel carburetors and throttle bodies
• Includes o-rings

Calflow manifolds are cast in high pressure steel dies rather than the pour-in sand molds used by other aftermarket manifold manufacturers. This type of tooling costs 2-3 times more than conventional sand-cast patterns, but the finished product is worth the additional expense. And because the cores (which form the internal ports and water passages) are mounted in steel instead of sand during the casting process, there is no chance of any core shift, which sometimes go undetected in sand castings.